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From: ram@zedat.fu-berlin.de (Stefan Ram)
Newsgroups: comp.lang.python
Subject: Re: Any way to "subclass" typing.Annotated?
Date: 29 Jan 2025 13:48:00 GMT
Organization: Stefan Ram
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Expires: 1 Jan 2026 11:59:58 GMT
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ram@zedat.fu-berlin.de (Stefan Ram) wrote or quoted:
>Option 2: Custom Wrapper Class

  To compile, this should read:

  Python

from typing import Annotated, TypeVar, Generic, Any

# Your trusty "abstract" flag, chillin' like it's at Venice Beach
abstract = object()

# Type variable, as constant as the NorCal fog
T = TypeVar("T")

class AbstractClassVariable(Generic[T]):
    def __class_getitem__(cls, item: T) -> Any:
        return Annotated[item, abstract]